When you're building a larger signal system such as within a station the Trackman's Goggles quickly become useless due to the fact that all the particle trails look the same.

It would be a lot more useful if there were different colors. Then it'd be a lot easier to follow a trail from one end to the other even if it happens to be close to other trails.

Alternatively/additionally there could also be different particles. This may be more colorblind friendly as well as additionally enhance ones ability to distinguish between the trails.

This appears to have been implemented in 9.7.0.0